Beshyah S A, Sharp P S, Gelding S V, Halliday D, Johnston D G
Unit of Metabolic Medicine, St Mary's Hospital Medical School, London, UK.
Acta Endocrinol (Copenh). 1993 Aug;129(2):158-64. doi: 10.1530/acta.0.1290158.
This study has investigated protein metabolism in adults with hypopituitarism before and after growth hormone (GH) replacement and in matched controls. Whole-body leucine turnover was measured in 16 GH-deficient adult hypopituitary patients (nine females and seven males) on standard thyroid, adrenal and sex hormone replacement and in 20 normal controls using primed continuous infusion of L-[1-13C]leucine. In seven of the patients, leucine turnover was restudied following 6 months' treatment with biosynthetic human GH (0.025-0.05 IU/kg body wt daily, with the final dose determined by patient tolerance). Compared with normal controls, hypopituitary patients had significantly reduced leucine flux (mean +/- SD: 97.8 +/- 24.9 vs 131.0 +/- 23.0 mumol.h-1 x kg-1; p < 0.001), reduced leucine incorporation into protein (80.4 +/- 20.9 vs 108.8 +/- 19.6 mumol.h-1 x kg-1; p < 0.001) and reduced leucine oxidation (17.4 +/- 4.8 vs 22.2 +/- 8.1 mumol.h-1 x kg-1; p < 0.05). Leucine turnover was similar in male and female patients. In the patients, leucine flux correlated positively with body weight (rho = 0.51, p < 0.05) and leucine incorporation in protein correlated positively with lean body mass (rho = 0.55, p < 0.05) and in male patients leucine flux correlated positively with serum insulin-like growth factor I (IGF-I) levels (rho = 0.71, p < 0.05). No significant relationship was observed with age or duration of hypopituitarism. Growth hormone replacement therapy did not produce a uniform effect on leucine metabolism. Mean values of leucine flux, oxidation and incorporation into protein increased, although the differences were not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)
本研究调查了生长激素（GH）替代治疗前后垂体功能减退症成年患者以及匹配对照组的蛋白质代谢情况。采用L-[1-13C]亮氨酸的首剂持续输注法，对16例接受标准甲状腺、肾上腺和性激素替代治疗的成年垂体功能减退症GH缺乏患者（9例女性和7例男性）以及20例正常对照者进行了全身亮氨酸周转率的测定。其中7例患者在接受6个月的生物合成人GH治疗（每日0.025 - 0.05 IU/kg体重，最终剂量根据患者耐受性确定）后，再次进行亮氨酸周转率的研究。与正常对照组相比，垂体功能减退症患者的亮氨酸通量显著降低（均值±标准差：97.8±24.9 vs 131.0±23.0 μmol·h-1·kg-1；p < 0.001），亮氨酸掺入蛋白质的量减少（80.4±20.9 vs 108.8±19.6 μmol·h-1·kg-1；p < 0.001），亮氨酸氧化减少（17.4±4.8 vs 22.2±8.1 μmol·h-1·kg-1；p < 0.05）。男性和女性患者的亮氨酸周转率相似。在患者中，亮氨酸通量与体重呈正相关（ρ = 0.51，p < 0.05），亮氨酸掺入蛋白质与去脂体重呈正相关（ρ = 0.55，p < 0.05），在男性患者中亮氨酸通量与血清胰岛素样生长因子I（IGF-I）水平呈正相关（ρ = 0.71，p < 0.05）。未观察到与年龄或垂体功能减退症病程的显著关系。生长激素替代治疗对亮氨酸代谢未产生一致的影响。亮氨酸通量、氧化以及掺入蛋白质的均值有所增加，尽管差异无统计学意义。（摘要截取自250字）
